Investigating the synergistic effects of tannic acid and tamoxifen in SKBR3 cells with the approach of HER2, EGFR expression and apoptosis induction by real time PCR and flow cytometry methods

HER2-positive breast cancer is one of the most aggressive subtypes of breast cancer, accounting for approximately 30% of all diagnosed cases. These cases of cancer are associated with decreased survival, tumor invasion, and overall poor prognosis. Unfortunately, a large number of patients are resistant to conventional treatments. Various reports have shown that tamoxifen has a response rate of 10-15% in estrogen-negative and HER2-positive tumors. The use of natural chemical sensitizers in combination with chemotherapy drugs can provide promising help in cancer treatment by increasing the effectiveness of chemotherapy drugs.

In this study, the chemical sensitization effect of tannic acid with tamoxifen was investigated in SKBR3 cells using real time PCR and flowcytometry tests.

According to the obtained results, it was found that tamoxifen and tannic acid alone cannot significantly reduce the expression level of HER2, but their combination causes a significant decrease in the expression level of EGFR and HER2. Also, the results of flow cytometry showed that the combination of tannic acid with tamoxifen caused a significant increase in the percentage of apoptosis compared to the control group, tamoxifen and tannic acid alone.

In general, it can be concluded that tannic acid can act as a chemical sensitizing polyphenol in combination with tamoxifen and is a promising option for clinical use.